Most ostomates employ some type of bag or pouch system to collect bodily wastes discharged from their surgically created stoma. Today, such pouches are generally formed of light weight, odor proof, flexbile polymeric materials and the collection systems are designed to be inconspicuous and permit the ostomate to engage in normal physical activity. However, many ostomates, particularly immediately following surgery, have fears concerning their ability to resume a "normal life". These fears center around worries that the collection system will leak or that odor will escape and that the system will be noticeable even through their outer clothing. Part of these problems are due to the discharge of flatus into the pouch which can cause an embarrassing distention of the pouch.
In order to overcome the problem of gas build up within the collecting system, it had been suggested to provide a vent opening either in the pouch or in the portion of the device which attaches to the body. Devices having simple vent openings are shown in U.S. Pat. Nos. 2,496,175; 3,055,368; 3,089,493; 3,865,109 and 4,185,630. Other devices have combined vent openings with filtering or deodorizing means as note U.S. Pat. Nos. 2,555,086; 3,439,677; 3,759,260; 3,804,091; 3,952,727 and British Pat. No. 1,541,565 and British Patent Application No. 2,031,282.